Question

CH3-CH3->CH3-CH2CL->CH2=CH2->CH3-CH2-OH

Answer 1

CH4+Cl2=CH3Cl+HCl
CH3Cl+2Na+CH3Cl=CH3-CH3+2NaCl
С2Н6+Cl2-> C2H5Cl+HCl 
C2H5Cl+NaOH->C2H5OH+NaCl
 C2H5OH (H+. Hg. t>140)=C2H4+H2O
C2H4+H2=CH3-CH3